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Fatigue properties of 40NiCrMo7 low alloy steel in the high cycle region were tested by rotating bending fatigue loading (f = 40 Hz, T = 20 5 , R = -1) on notched specimens after application of shot peening surface treatment (cast steel balls with diameter of 0.43 mm, Almen intensity 12A, coverage 100 % and consequently the surface was re-peened with glass beads to decrease the final roughness). The compressive residual stresses created by shot peening increased the time necessary for fatigue crack initiation what in the final case increased fatigue properties. The fatigue limit σc was higher for almost 28 % in the case of notched shot peened specimens.

Comparing with one directional magnetic treatment, a multidirectional magnetic treatment is applied to reduce residual stress in thin-walled bearing rings in order to improve the dimensional stability of bearing rings. The magnetic field was applied in both the axial and the radial directions of the thin walled bearing rings respectively. Six months of repeated testing results demonstrated that the dimension of bearing rings after magnetic treatment had no significant change. Experimental results shows both the major axis(the longer axis of an ellipse)and the minor axis(the shorter axis of an ellipse)appear shorten tendency and the dimension of bearing rings tends to be stable. Thin-walled uniform radial pressure deformation formulas are applied to calculate the reduced stress, and the maximum reduction is up to 45.97MPa. Research shows the multi-directional magnetic treatment can improve the dimensional stability of bearing rings and used in practical engineering.

Industrial laser marking of the parts is used for the long life identification. For these the micro engraving and annealing are used. The main requirements for the marking are visibility, readability, stability and especially surface without surface modification or defects. In case of the cutting tools main marking are made on the cutting tool shank so it is necessary to use the correct parameters of the marking setup. The marking must be made without change of accuracy and surface quality. When the bad parameters are used the sharp edges are created on the edge of the descriptions. These edges cause gradually damage of the clamping surface and it causes gradually loss of clamping accuracy. So it is a very important to use optimal parameters which depend on the marking material. These article deal with process optimization of the laser marking parameters when the sintered carbide and cermet are used. The laser parameters like laser power, scanning speed and frequency were change and surface quality was evaluated by the optical microscope IFM G4.

The paper deals with a study of actuator (brake cylinder) modification for generation of braking force in a brake unit. The original solution, carried out using the original brake cylinder in cooperation with the proportional pressure control valve, is sufficient in terms of correct function of the brake unit, but in terms of safety, the corresponding force sensor may be damaged in case of a control circuit proportional pressure valves defect. Another reason for the study is utilization of the total regulation range of the proportional pressure valve and improvement of the brake unit response time in case of braking force overload. Such overload results in tread or rotating rail surface damage. The article gives description of the currently implemented passive measures to increase safety against sensors damage, but also of proposed active measures to eliminate these defects by changing size and type of the brake cylinder.

Lean duplex stainless steels were developed for use in environments where high strength and corrosion resistance are required. Duplex stainless steels offer a cost-effective solution with high strength and corrosion resistance. Due to high chromium content and a balanced composition, 1.4362 ferritic-austenitic stainless steel possesses excellent corrosion resistance in acidic environments. General corrosion problems in duplex stainless steels at 475°C have been widely researched. Steels are most degraded at 475°C, but corrosion can still occur at both lower and higher temperatures. Corrosion resistance is influenced by chromium content and microstructural morphology. The percentage of each phase and its properties are determined by composition, technological processing and heat treatments. Machining and fabrication practices, such as welding, are also vital for performance. The objective of this study was to determine the effects of 30-minute isothermal heat treatments at 535°C and exposure time on relative mass loss and roughness parameters of 1.4362 lean duplex stainless steel. The influence of boiling nitric acid on the corrosion resistance of steel was investigated based on mass loss and roughness parameters. Corrosion properties and roughness of 1.4362 alloys are discussed in this paper.

NiTi alloy exhibits the shape memory effect, which implies the application in medicine and also many industrial branches. This paper is devoted to the manufacture of these alloys by the use of powder metallurgy using reactive sintering. This method could enable easier production of this alloy and achievent of higher purity. However, for the optimization of this technology, the deeper knowledge of the mechanism of the process is needed. This work uses microscopy on real powder mixtures subjected to reactive sintering, as well as on model samples processed under various conditions.

The paper deals with the influence of charge composition on microstructure, mechanical and fatigue properties of synthetic nodular cast irons and their micromechanisms of failure. The basic charge of experimental melts was formed by a different ratio of pig iron and steel scrap. Chemical composition of individual melts was regulated alternatively by silicon carbide (SiC) or ferrosilicon (FeSi) and carburizer. The specimens from three melts of nodular cast iron with different microstructure and mechanical properties were used for experiments. Fatigue tests were realised at low frequency sinusoidal cyclic push-pull loading (stress ratio R = -1) at ambient temperature (T = 20 ± 5 °C). They were carried out with using the fatigue experimental machine Zwick/Roell Amsler 150HFP 5100 at frequency f ≈ 120 Hz.

The article deals with the results of the simulation analysis of a railway wagon bogie model. We analysed four freight wagon bogie variants for its dynamics properties research. The bogie models correspond in general to the Y25 bogie concept. The models were created in SIMPACK software enhanced by the RAIL module. From the research results depicted in the graphs we found out, that the newly designed bogie variant gives the best results when compared to the other analysed versions. The newly designed model consists of a standard Y25 bogie frame with two Lenoire friction dampers. This bogie is equipped with longitudinal linkages on both sides. These linkages are completed with a radial torsion binding, torsion rod, between side bogie parts. The contact of railway wheels and rails generates active forces affecting the surface contact, affecting the size of the normal and tangential stress, wear surfaces of the wheel/rail, or directly the size of the derailment.

Parametric modelling based on mathematical relationships allows creation of different variants of proposed solutions in real time. In particular, parametric modelling enables rapid design of 3D virtual models intended for further analysis and simulations. This paper presents an approach to design of a six strand wire rope model in a CAD environment. The presented model is characterized by double helical winding wires. Wires axes curves are mathematically expressed in the form of parametric equations. The parametric equations used in model generation are presented and the whole methodology of rope model creation in CATIA V5 software is briefly described.

An article deals with an analysis of selected aspects of heat-treated bearing rings during machining and comes up with a solution (a machining operation) leading to improving efficiency of a machining process (i.e. an elimination of a generally expensive cutting technology when the same surface integrity is kept) lying in the series of samples that would be tested experimentally under university conditions (a workroom C2 of Department of Machining Technology FSI VUT in Brno) using a CNC turning lathe SP 280 SY.
A theoretical part focuses on a characteristics and analysis of a given component including an applied material 100Cr6 from which bearing rings are made. A practical part deals with an analysis and evaluation of a residual tension in a surface layer (Barkhausen noise: BN) using the device Rollscan 350. The article also comes up with a solution of an issue of surface integrity after a turning operation of bearing rings. The surface integrity is analysed with a touch measuring device (the device with an inductive sensor Form Talysurf Intra - Taylor Hobson) and a contactless device Talysurf CCI Life - Taylor Hobson.
The article ends with an analysis and evaluation of assessed aspects applied during turning of heat-treated bearing rings regarding the required workpiece quality.

The possibilities for reparation by hard facing of the damaged working parts - the hammers of the secondary stones crusher are investigated in this paper. The analyzed crusher is stationary and it belongs into a group of the process equipment aimed for producing the crushed stone. The produced stone is later used for manufacturing various construction materials like asphalt, concrete, etc. Wear of the crusher's working parts occurs during the exploitation due to operation with very hard materials. That wear is usually abrasive and of high intensity what causes failure of the working parts and consequently the machine's downtimes and appearance of various types of losses, primarily financial ones. To prevent that, and to reduce the downtimes as well, one uses reparation technologies, one of which is hard facing. The analysis of the mass losses of the hard faced parts, after certain number of hours of the crusher's field operation, is performed in this paper.

Final properties of castings made of aluminium alloys strongly depend on amount of impurities. Production of high quality parts thus requires strict control of impurity level or elimination of detrimental effects caused by presence of impurities. Such requirements are even more important in case of castings made of recycled materials. In Al-Si based alloys is very important awareness of the problems with the presence of iron as an impurity. Negative iron effect is expressive even in low amounts, and with higher level becomes more harmful. Elimination of its effects can be performed by several techniques, from which no one have general implementation. One of the possible ways is addition of so called iron correctors to the alloys. Influence of vanadium as iron corrector is still not precisely examined. In this article, influence of vanadium to AlSi10MgMn alloy with 1.0 wt. % of iron is analysed by tensile and hardness testing together with microstructural evaluation.

Different types of aluminium systems are popular in building industry. Manufacturing technology of such products is a very important factor influencing the final result of production and hence the cost of production. Good quality of these systems results in good quality of investment where they are used. There is big competition on aluminium system market. The product competition decides about the existence of the manufacturer on the market. Therefore, it was decided to use the 3x3 matrix to evaluation manufacturing technology of aluminium systems produced by chosen Polish company for building industry. This matrix can be easily used to evaluate the technology of any aluminium products. From the analysis presented in the paper it results that the research company is located in area 9 of the 3x3 matrix, i.e. "Search for occasions", and the factors which decided about this position were evaluated by staff at the medium level.

The article deals with the measurement on CMMs with tactile stylus system. Accuracy of CMM is mostly indicated by the parameter MPEE (Maximum Permissible Error for length measurement). This parameter refers to an errors during the measurement of distance between two points in space. Verification of MPEEparameter is described in an ISO standard 10 360-2 Acceptance and re-verication tests for coordinate measuring machines. These acceptance and re-verification tests are often conducted with a short and stiff reference stylus which is not and also mostly cannot be used in real measurements. On the contraryin applications such as a measurement of engine blocks and transmission housings very complex styli configurations are used. The influence of stylus system configuration on the variability of measurement when using long extensions, different materials (aluminium, carbon fiber composites) and high scanning speed in not described. The aim of this article is to design a methodology for testing the styli systems used in complex metrology applications in quality control of hi-precision mechanical components, to analyze the contribution of stylus system configuration to the measurement system variability in the form of a standard measurement uncertainty described by standard deviation.

Standardization is the basis for improvement in the company. This allows for repeatability performance of activities and thus the stability of the process. This chapter presents the standardization as part of Toyota's production system. Standardization is also one of the elements examined using the method BOST, because it was used for hot dip galvanizing process improvement. The research was carried out in one of the national companies producing steel products and providing services in the field of modern anti-corrosion protection, in particular hot-dip galvanizing.

The article describes the vehicle passability testing possibilities by the help of computational simulation with the usage of computing simulation system ADAMS AVT. The simulation calculations can help to find quick answers to basic and additional questions of design change influences in the area of testing vehicle passability. The first part of the article contents description of partial computation simulation models construction which the calculations are associated with. The binding conditions of calculations are mentioned also. In the second part of the article, there are mentioned and evaluated the results of performed simulation calculations. These calculations are performed in order to find out an influence of operation conditions on the vehicle passability. Real operation condition is invasive vehicle speed into a slope in this case. Under investigation is the change of the gradient angle uphill maximum and beaten distance uphill that is the vehicle able to overcome.

An analysis of the friction time influence on creation and structure of the mixing zone during the friction welding process of the two dissimilar steels is presented in this paper. The changes were monitored on the two welded samples, made of the highly-alloyed steel HS 6-5-2-5 and the high carbon C60 steel. The objective of this work was to show how the mixing zone is created and to point to its influence on the quality of the whole welded joint, since it is characterized by the inhomogeneity of the microstructure and the chemical composition. Those problems arise due to the thermal and deformation conditions, so during the experiment the welding pressure (70-90 MPa) and the welding time (3-18 s) variations were monitored. Experimental results have shown that the shape and the structure of the friction zone are strongly dependent on the friction time and that by its variation one can obtain the desired structure and thus the quality of the friction welded joint. Based on obtained results the minimum value for the friction time is recommended.

This work deals with the problematics of 3D printing. Additive manufacturing (AM) covers a lot of principles of producing products and prototypes, for example, Direct Metal Laser Sintering (DMLS). This principle is based on sintering metal powder in thin layers, layer by layer. This theme is very extensive and a very popular research area. The paper is focused on printing thin walls. The material for printing was Maraging Steel MS1. This material achieves great mechanical properties like as high strength and high hardness. The tensile strength can be up to 2000 MPa after age hardening. The printer used was an EOS M290. The effects of different part position on safety of printing are compared. Also, the effect of support structures on accuracy was investigated. The main part of the paper is focused on an experiment where thin walls are printed and subsequently evaluated. The influences and limitations were investigated. The measurements were carried out on a Blickle Multicheck PC500 microscope.

Powder metallurgy could be an alternative way to ordinary casting technologies in the processing of aluminium alloys with high content of iron. Far more attention is given especially to technologies capable to produce ultrafine microstructures leading to desired mechanical properties. Binary alloy of aluminium and iron (AlFe 17 wt. %) was prepared by mechanical alloying, centrifugal atomization and mechanical working followed by consolidation via spark plasma sintering and hot extrusion. Phase composition of the compact samples consisted of solid solution of iron in aluminium and of intermetallic phase identified as Al13Fe4. Very fine microstructure was achieved by combination of mechanical alloying and subsequent consolidation via spark plasma sintering and by combination of centrifugal atomization and hot extrusion. Compressive strength of these samples was 508 MPa and 637 MPa, respectively. Moreover, the AlFe17 alloy prepared by combination of centrifugal atomization and hot extrusion exhibited extraordinary ductility reaching almost 36 %.

Using of cutting inserts is currently a normal part of the manufacturing process. The article deals with structural analysis and material selection of inserts for turning. Analysis of the composition of experimental inserts was made by electron microscopy, namely EDS analysis. EDS analysis is an analysis using an energy dispersive spectrometer. For this purpose was used EDS analyzer Bruker 16 which is part of a scanning electron microscope Tescan Vega 3. These analysis can provide a good picture of the structure and construction of inserts and their composition. This may assist in finding suitable cutting conditions. These analyzes were performed in other experiments performed at the Faculty of Production Technology and Management at Jan Evangelista Purkyně University in Ústí nad Labem.

The field of material surface modification with aim of biomaterials construction involves several approaches based on surface treatments that allow to prepare materials, which support the cell adhesion and proliferation and thus aid and improve the tissue formation. Modified materials have a surface composition and morphology intended to interact with biological systems and cellular functions. Not only surface chemistry has an effect on material biological response, surface structures of different morphology can be constructed to guide a desirable biological outcome. Nano-patterned material surfaces have been tested with aim to determine how surface geometry, physical and chemical properties on a micro- and nano-scale can affect cellular response and influence cell adhesion and proliferation. Surface physico-chemical properties (e.g. chemistry, morphology, wettability, electrical conductivity, optical and mechanical properties) of treated surfaces were determined. The enhancement in cell adhesion and proliferation on modified substrates was studied in vitro. Bactericidal action of noble metal nano-particles (e.g. Au, Ag) on polymers was characterized. The influence of metal nano-particles grafting by using metal nano-particle suspension prepared by "green" methods was determined.

Selective laser melting (SLM) as a representant of additive manufacturing technology brings about many advantages into production, which are appreciated especially in the field of biomedical applications and implantology. Our paper is focused on characterization of titanium alloy Ti-6Al-4V (Ti Grade 5) widely used for orthopaedic implants produced by this novel method. Microstructure and mechanical properties are compared with the same material prepared by conventional way of casting, forging and machining. Results show these are almost equivalent. Microstructure is in both cases formed by two phases +, but possesses different morphology. Yield strength and ultimate tensile strength of SLM material slightly overpassed values obtained by conventional commercial production (950 MPa and 1000 MPa vs. 877 MPa and 985 MPa). Only elongation was reduced resulting from the presence of some porosity. However, by future optimalization of SLM process parameters, porosity is expected to decrease.

Hard inorganics microparticles are added to the composite systems due to optimization of some mechanical properties among which is possible to rank hardness and resistance to abrasive wear. Advantage of interaction of metal powders with polymers is also their ferromagnetism which changes physical properties of resulting composite systems. This paper is focused on evaluation of mechanical properties of epoxy resin filled with microparticles on the basis of iron powder (20.6 μm), mainly on resistance to abrasive wear, hardness and on adhesive and cohesive characteristics. The experiment evaluates composite systems prepared without using controlled semi-layers and without using a vacuum technology. Such technology was chosen with regard to practise. It is possible to consider the adhesive and cohesive characteristics as key properties determining possible application areas of filled reactoplastics. For evaluation of fracture areas was used electronic microscopy. The experiment confirmed significant increase of resistance to abrasive wear with increasing concentration of iron powder. This property can be utilized in widening the application areas of reactoplastics resins, i.e. creating the new resistant layers.

The article deals with the basic steps of injection mould design. The goal of the research was the proposition of the mould form so to be achieved the minimum waste and the shortest time of both mould filling and product cooling. Studied mould component is intended to serve as a stopper in the automotive spotlight. The simulations were realized for three designed types of running system and for four versions of cooling system. Due to the design optimization, the pressures, originated inside the cooling system and inside the mould cavity during the injection moulding process, were also investigated. 3D model of the mould was created in Autodesk Inventor Professional software and then solidification of material was simulated in Autodesk Moldflow. On the basis of the best solution, real form was manufactured and placed into injection moulding machine Arburg Allrounder 320 C.

In the aerospace industry, the nickel-based superalloys are often used due to their ability to withstand extreme conditions. They find their use particularly as turbine blades in jet engines. An important example of this type of superalloy is INCONEL. This construction material must meet a wide range of complex requirements with regard to its properties and technological and operational characteristics that are required by the heavy duty in extreme conditions.
The INCONEL Superalloys represent multicomponent and multiphase materials with their complex alloying base and structure with distinct dendritic segregations. Their long life and reliability in operation are directly related to the microstructure, or to its stability in a long-term operational application, respectively.
The presented work deals with the evaluation of microstructural parameters at two variants of cast superalloy INCONEL 713LC, applying the light microscopy and electron microscopy, including the fractographic analysis.

The automotive brake (clutch) disks are produced almost exclusively from flake graphite cast iron. These disks must fullfil a variety of strictly controlled parameters - high wear resistance, hardness, resistance against thermal fatigue and good thermal conductivity. The microstructure is created by the IA graphite in pearlite matrix. The isothermal hardening to ausferrite structure (AGI) was made in order to improve standard flake graphite cast iron properties. New methods and procedures of non-destructive structuroscopy, magnetoinductive, ultrasound and magnetic spot methods were used to compare material properties of flake graphite cast iron and ADI. By these methods, elasticity modulus, strength and hardness were evaluated. The resistance against thermal fatigue was evaluated by the Eichelberg factor. In this contribution, Material parameters of standard flake graphite cast iron and AGI are compared. The heat treatment of brake disk matrix from AGI can considerably improve their material parameters, especially durability.

In this article is described, how can ultrasonic method Phased Array be used for inspection of weld joints made by electrofusion welding on plastic pipelines. For purpose of testing and to develop a proper setup, several artificially made defects were created in the weld area to verify, if this method can be successfully used for this application, since standards for testing of plastic pipelines have no specific regulation for this method. Therefore we are trying to propagate this method for gas and water transport industry, because it can severely reduce risks of accidents caused by unidentified defects, which can occur in welded joints.

This work deals with fatigue testing of the EN S355 structural steel welded joint. The weld was manufactured by the MIG welding technology and as the filler material was used the G3Si1 wire. The fatigue tests were carried out in the rotating bending mode on the specimens manufactured from the welded joint of the S355 steel. The main aim was to evaluate the fatigue endurance of the weld material and for this reason were used machined axis symmetrical specimens to remove the notch effect of the weld shape. In order to increase the fatigue endurance of the weld, the Nd-YAG laser was used for laser shock peening (LSP) of specimens surfaces, which lead to removing of the weld defects but in overall caused that LSP has behaved as the notch and lead to decreasing of the fatigue endurance. Obtained results of fatigue tests are compared, discussed and supported by correlation with results of additional experiments, e.g. identification of incurred structures after the laser shock peening by the metallographic observations and micro-hardness tests.

High pressure die-castin of aluminum alloys is a complicated process depending on a number of factors which relate between each other. That is why these factors must be regulated in the process of casting. This contribution focuses on the possibilities of eliminating the defects of short run. This defect is located on the edge of the flow opening of the casted body STIRNPLATTE 033. From the view of functionality this kind of defect is inadmissible. Experimental castings from the AlSi12CuNiMg alloy were casted by using different technological parameters where the work surface temperature of the mould and the profile layout of the piston path differed. Experimental measurements of the mechanical properties and RTG analysis were conducted. From the measured values it is possible to state that by infringing the optimal temperature in the mould and the incorrect setting of the piston path parameters has the biggest influence on the amount of misruns.

The paper presents the research results of the various coatings deposited using the cathodic arc evaporation Physical Vapour Deposition (PVD) method at 300°C, suitable for application on temperature-sensitive steels and alloys. Three main groups of coatings are deposited, denoted as E1, E2 and E3. The deposited bi-layer numbers for E2, E3 and E4 are 103, 207 and 107, respectively. Each group consists of two subgroups, S1 and S2, TiN/AlTiN and AlTiN/TiN nanomultilayer (NML) coatings, respectively. The coating deposition time for E1 and E2 is 60 min, and the carousel rotation speed is 35s and 17.5s, respectively. The coating thicknesses for these two coatings groups are 2.4 μm and 2.3 μm, and the calculated bi-layers thicknesses are 23.3 nm and 11.6 nm, respectively. TiN/AlTiN and AlTiN/TiN as NML or superlattice coatings are deposited onto high-speed steel substrates using pure titanium and aluminium-titanium (70/30 at. %) cathodes. Tribological testing is conducted using an Al2O3 ball and a ball made from steel ISO 683/13, and the applied load and path length at the used speed of 60 RPM are 10N and 25m, respectively. Measurements are performed at room temperature and a humidity of 44 ± 2%.